Torenia's bright and quirky upturned flowers give rise to many common names. If you've ever seen one looking at you, you will understand the name "clown flower." Another common name, "wishbone flower," comes from the way the anthers arch and join at the tip when the flowers first open. Visiting bees break that wishbone while pollinating. Finally, the name "bluewings" refers to the common blue-purple tips on the certain hues of the petals.
Torenia is a profuse blooming annual flower that starts flowering early in the season and keeps up the show through fall, with minimal deadheading. The plants are deer-resistant and attractive to hummingbirds. They are a good choice for borders.
|Botanical Name||Torenia Fournieri|
|Common Name||Wishbone flower, Bluewings|
|Plant Type||Annual flowering plant|
|Mature Size||6 to 12 inches tall, 6 to 9 inches wide|
|Sun Exposure||Partial shade, full shade|
|Soil Type||Loamy, well-drained|
|Soil pH||6.0 to 6.5|
|Bloom Time||June to frost|
|Flower Color||Blue-purple, white, pink with yellow markings|
|Hardiness Zones||2 to 11|
How to Grow Torenia
Start torenia seeds about six to eight weeks before the last frost date. Torenia does not transplant well, so seeds should be started in peat or paper pots. Don't cover the seeds with soil, as they need light to germinate. Keep the soil moist and relatively warm—around 70 degrees Fahrenheit—until the seeds germinate. After that, they can handle cooler temperatures. Pinching the growing tip when it reaches a couple of inches high will help to create a bushier plant.
In frost-free climates, Torenia can be direct-seeded outdoors, about one week before your last expected frost date. Aside from keeping torenia well-watered and fed, there isn't much maintenance necessary. There's really no need to deadhead. They will keep on blooming unless it gets too hot for them to set buds.
Torenia can be susceptible to fungus diseases that will affect their leaves and stems. Keeping them watered and cool and providing good air circulation, so the leaves don't stay wet, should prevent most problems.
Torenia flowers are adaptable to many locations; however, the ideal spot gets morning sun and afternoon shade. If you're planting in a location that's very hot, particularly in the summer, lean toward putting torenias in a shady location.
These flowers aren't particular about soil pH, but they do prefer it to be slightly acidic—between 6.0 and 6.5, if possible. The ideal soil is loamy, rich, moist, and well-drained. When planting torenia, dig in one to two inches of compost to improve the quality.
Keep the soil of wishbone flowers moist but not soggy. The plant is susceptible to root rot.
Torenia flowers grow best in 70 to 75 degrees Fahrenheit during the day and 65 to 70 degrees at night. While the plant is growing, cooler temperatures in the morning will help prevent stretch. Although it's classified as a warm-weather annual, torenia doesn't prefer hot or humid weather.
To keep torenia flowers prolific and blooming, provide a balanced, all-purpose plant food every two to three weeks. Aim for a 10-10-10 balance or 20-20-20 balance. If you're feeding with liquid fertilizer, fertilizer twice a month throughout the growing season with a ratio of a tablespoon of fertilizer concentrate with a gallon of water.
Potting and Repotting
Torenia plants do not like being transplanted, so it's best to plant them in the peat or paper pots in which they were seeded until they are planted outdoors. To prevent disturbing the roots when you move them to the garden, you can plant them pot and all. Always harden off the plants gradually, before placing outside.
To propagate torenia, start by clipping cuttings that are at least six inches long. Try to get a node at the bottom of the stem, which is more likely to root. Remove any leaves that rest below the water line to avoid rot.
Once a root system begins to grow, plant the roots in a pot filled with potting soil or homemade compost, and then harden off for a few days. Then, you can plant it in the garden.
Deadheading torenia flowers isn't absolutely necessary, though picking off spent blossoms can encourage more growth. If the plant looks scraggly, clip it back to about half its height.
Common Pests and Diseases
Torenias often fall prey to common pests and diseases, including:
- Botrytis: This disease is characterized by gray mold on the plant. Remove the affected plant parts and make sure there's good air circulation around the plants.
- Powdery mildew: This disease is caused by a fungus that gives leaves a powdery white appearance. Prune the affected areas and use an appropriate fungicide. This disease rarely kills plants, but it can be prevented by making sure air circulation is good. It is more likely to occur in humid weather, or when plants are watered from overhead, splashing the spores up from the soil onto the leaves.
- Aphids: These tiny sucking insects that spread disease as they feed on the bottom of the leaves. The presence of ants on plants often indicates the presence of aphids, since they feed on the "honeydew" excretions produced by the aphids. Use insecticidal soap or wash them off with a strong spray.
- Whitefly: These are tiny flying insects that you can see rise up in a cloud when the plant is disturbed. Control these with hot pepper wax or insecticidal soap.